The Church’s conscientious effort to resist this pressure calls for a reasoned defense of marriage as a natural institution consisting of a specific communion of persons, essentially rooted in the complementarity of the sexes and oriented to procreation. Sexual differences cannot be dismissed as irrelevant to the definition of marriage. Defending the institution of marriage as a social reality is ultimately a question of justice, since it entails safeguarding the good of the entire human community and the rights of parents and children alike.

When addressing itself to public debate, in other words, the Church should make reasoned arguments, not proclaim revealed truth. Within the Church, however, the Pope suggested a more pastoral approach. “In this great pastoral effort,” he said, “there is an urgent need for the entire Christian community to recover an appreciation of the virtue of chastity. … It is not merely a question of presenting arguments, but of appealing to an integrated, consistent and uplifting vision of human sexuality.” Of course, these two approaches — reasoned argument and pastoral care — are not mutually exclusive; I don’t understand him to say that reasoned argument is out of place within the Church, or that more intuitive appeals are out of place in politics. The Pope appears to understand, though, that different appeals may be appropriate in the public square and within the Church itself.